Concrete pole

ABSTRACT

In a method of reinforcing an existing concrete electric pole having an annular side wall, an inner hollow portion provided therein and an opening portion formed to a position of the annular side wall to be penetrated therethrough, at least one of a predetermined amount of mortar, a predetermined amount of sand and a predetermined amount of gravel is injected into the inner hollow portion of the electric pole through the opening portion. A reinforcing member for reinforcing the electric pole is injected into the inner hollow portion of the electric pole through the opening portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an existing concrete electric pole, ajig for arranging a reinforcement member in the existing concreteelectric pole and a method of reinforcing the existing concrete electricpole.

2. Description of the Related Art

An existing concrete electric pole is already installed so that itslower portion is arranged under the ground and its upper portion isarranged above the ground.

In cases of reinforcing the existing concrete electric pole for dealingwith the aging change thereof and so on, there is adopted a conventionalreinforcing method of winding a reinforcement member such as an aramidfiber seat or the like around an outer periphery of the concreteelectric pole.

The electric concrete pole is usually reinforced in the range of itsunderground lower portion including its boundary portion with respect tothe surface of the ground to its upper portion.

That is, when reinforcing the concrete electric pole by using theconventional reinforcing method, it is necessary to excavate the surfaceof the ground around the boundary portion of the concrete electric poleso as to expose the underground lower portion of the concrete electricpole.

Depending on the installed location of the concrete electric pole,structures which are adjacent to the concrete electric pole must beremoved. For example, in a case where a wall around a house is close tothe concrete electric pole, the wall must be removed. In addition, in acase where the surface of the ground around the boundary portion of theconcrete electric pole is inclined and a stone wall or the like standson the inclined surface in which the concrete electric pole is installedmust be demolished.

The demolition works of the structures and the restoration works of newstructures in place of the demolished structures require much time,causing the total time of the reinforcing work and the total costthereof to be increased, respectively.

SUMMARY OF THE INVENTION

The present invention is made on the background of the foregoingcircumstances. Accordingly, it is an object of the present invention toprovide a concrete electric pole, a reinforcement member arrangement jigin the concrete electric pole and a method of reinforcing the concretepole, which are capable of easily reinforcing the concrete electric poleas compared with the conventional reinforcing method.

According to one aspect of the present invention based on the object,there is provided a method of reinforcing an existing concrete electricpole having an annular side wall, an inner hollow portion providedtherein and an opening portion formed to a position of the annular sidewall to be penetrated therethrough, the method comprising the steps of:injecting at least one of a predetermined amount of mortar, apredetermined amount of sand and a predetermined amount of gravel intothe inner hollow portion of the electric pole through the openingportion; and injecting a reinforcing member for reinforcing the electricpole into the inner hollow portion of the electric pole through theopening portion.

According to another aspect of the present invention based on theobject, there is provided a method of reinforcing an existing concreteelectric pole having an annular side wall, an inner hollow portionprovided therein and an opening portion formed to a position of theannular side wall to be communicated to the inner hollow portion, themethod comprising the steps of: injecting at least one of apredetermined amount of mortar, a predetermined amount of sand and apredetermined amount of gravel into the inner hollow portion of theelectric pole through the opening portion; inserting a reinforcingmember for reinforcing the electric pole into the inner hollow portionof the electric pole through the opening portion; and injecting fillingmaterial into a gap between the inserted reinforcing member and theinner hollow portion.

According to further aspect of the present invention based on theobject, there is provided a method of reinforcing an existing concreteelectric pole having an annular side wall, an inner hollow portionprovided therein and an opening portion formed to a position of theannular side wall to be penetrated therethrough, the method comprisingthe steps of: preparing a jig member; inserting a reinforcing member forreinforcing the electric pole into the inner hollow portion of theelectric pole through the opening portion while the reinforcing memberis supported by the jig member; injecting at least one of apredetermined amount of mortar, a predetermined amount of sand and apredetermined amount of gravel into the inner hollow portion of theelectric pole through the opening portion; and while the insertedreinforcing member is supported by the jig member, injecting fillingmaterial into a gap between the inserted and supported reinforcingmember and the inner hollow portion.

According to still further aspect of the present invention based on theobject, there is provided a reinforced electric concrete pole reinforcedby the method according to one aspect of the present invention.

According to still further aspect of the present invention based on theobject, there is provided a reinforced electric concrete pole reinforcedby the method according to second aspect of the present invention.

According to still further aspect of the present invention based on theobject, there is provided a reinforced electric concrete pole reinforcedby the method according to third aspect of the present invention.

According to still further aspect of the present invention based on theobject, there is provided a jig for arranging a plurality of reinforcingmembers in an inner hollow portion of an existing concrete electricpole, each of the plurality of reinforcing members has one end portionto which a string member is connected, the jig comprising: a baseportion; a plurality of supporting members rotatably mounted on one endportion of the base portion, the supporting members have a substantiallyrod shape and same longitudinal lengths, respectively; a plurality ofthrough holes formed on both end portions of the supporting members,respectively, each of the through holes allowing each of the stringmembers to be put therethrough; and a locking member mounted on the baseportion, the locking member for releasably locking the supportingmembers.

According to still further aspect of the present invention based on theobject, there is provided a jig for arranging a plurality of reinforcingmembers in an inner hollow portion of an existing concrete electricpole, each of the plurality of reinforcing members has one end portionto which a string member is connected, the jig comprising: a base bar; asupporting member mounted on one end portion of the base bar, thesupporting member having a surface of substantially circular arc shape;and a plurality of suspending members mounted on the surface of thesupporting member, each of the suspending members having a through holeallowing the string member to be put therethrough.

According to still further aspect of the present invention based on theobject, there is provided a method of arranging a plurality ofreinforcing members in an inner hollow portion of an existing concreteelectric pole by using the jig according to claim 19, each of theplurality of reinforcing members being inserted in the inner hollowportion and having one end portion to which a string member isconnected, the method comprising the steps of: connecting other endportions of the string members to the through holes of the jig,respectively, inserting the supporting members into the inner hollowportion through the opening portion; rotating the supporting members sothat, when the plurality of supporting members are arranged at sameintervals among them in the rotational direction, the supporting membersare releasably locked by the locking member of the jig; and pulling theother end portions of the string members to be tensioned so that thereinforcing members are arranged in the inner hollow portion at sameintervals thereamong in the rotational direction.

According to still further aspect of the present invention based on theobject, there is provided a method of arranging a plurality ofreinforcing members in an inner hollow portion of an existing concreteelectric pole by using the jig according to claim 21, each of theplurality of reinforcing members being inserted in the inner hollowportion and having one end portion to which a string member isconnected, the method comprising the steps of: connecting other endportions of the string members to the through holes of the jig,respectively, inserting the supporting member into the inner hollowportion through the opening portion; handling the jig so as to arrangean axial direction of each of the through holes is substantially inparallel to the axial direction of the electric pole; and pulling theother end portions of the string members to be tensioned so that thereinforcing members are arranged in the inner hollow portion at sameintervals thereamong in a circumferential direction.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and aspects of the present invention will become apparentfrom the following description of embodiments with reference to theaccompanying drawings in which:

FIG. 1 is a partially longitudinal cross sectional view showing astructure of an electric pole which is already reinforced by areinforcing method according to a first embodiment of the presentinvention;

FIG. 2 is an enlarged perspective cross sectional view showing adetailed structure of the reinforcing portion of the electric pole shownin FIG. 1;

FIG. 3A is a flowchart showing a working procedure of reinforcing anelectric pole which has not been reinforced yet according to the firstembodiment;

FIG. 3B is a view pictorially showing the working procedure shown inFIG. 3A;

FIG. 4 is a partially longitudinal cross sectional view showing astructure of an electric pole which is already reinforced by areinforcing method according to a second embodiment of the presentinvention;

FIG. 5 is an enlarged perspective cross sectional view showing adetailed structure of the reinforcing portion of the electric pole shownin FIG. 4;

FIG. 6 is an enlarged perspective cross sectional view showing amodification of an electric pole according to the second embodiment;

FIG. 7A is a flowchart showing a working procedure of reinforcing anelectric pole which has not been reinforced yet according to the secondembodiment;

FIG. 7B is a view pictorially showing the working procedure shown inFIG. 7A;

FIG. 8 is a partially longitudinal cross sectional view showing astructure of an electric pole which is already reinforced by areinforcing method according to a third embodiment of the presentinvention;

FIG. 9 is an enlarged perspective cross sectional view showing adetailed structure of the reinforcing portion of the electric pole shownin FIG. 8;

FIG. 10 is a structural view showing a reinforcing member arrangementjig used for the reinforcing method according to the third embodiment;

FIG. 11 is a structural view showing a state of the jig shown in FIG. 10in which second and third supporting members are closed;

FIG. 12A is a flowchart showing a working procedure of reinforcing theelectric pole which has not been reinforced yet according to the thirdembodiment;

FIG. 12B is a view pictorially showing the working procedure shown inFIG. 12A;

FIG. 13 is a lateral cross sectional view at an upper side of a secondopening portion of the electric pole shown in FIG. 8 from a view of anupper side thereof, showing a state that aramid rods are inserted in aninner hollow portion of the electric pole shown in FIG. 8 according tothe third embodiment;

FIG. 14 is a lateral cross sectional view at an upper side of a secondopening portion of the electric pole shown in FIG. 8 from a view of anupper side thereof, showing a state that the jig is inserted in theinner hollow portion of the electric pole shown in FIG. 8 according tothe third embodiment;

FIG. 15 is a lateral cross sectional view at an upper side of a secondopening portion of the electric pole shown in FIG. 8 from a view of anupper side thereof, showing a state that the aramid rods are suspendedby the jig according to the third embodiment;

FIG. 16 is a perspective view showing an arrangement of the aramid rodsin the inner hollow portion shown in FIG. 8 according to the thirdembodiment;

FIG. 17 is a structural view showing a modification of the jig accordingto the third embodiment;

FIG. 18 is a partially longitudinal cross sectional view showing astructure of an electric pole which is already reinforced by areinforcing method according to a fourth embodiment of the presentinvention;

FIG. 19 is a structural view showing a first jig for arrangingreinforcing members used for the reinforcing method according to thefourth embodiment;

FIG. 20 is a structural view showing a second jig for arrangingreinforcing members used for the reinforcing method according to thefourth embodiment;

FIG. 21A is a flowchart showing a working procedure of reinforcing anelectric pole which has not been reinforced yet according to the fourthembodiment;

FIG. 21B is a view pictorially showing the working procedure shown inFIG. 21A;

FIG. 22 is a view showing a state that the first jig is inserted intothe electric pole shown in FIG. 18 according to the fourth embodiment;

FIG. 23 is a view showing another state that the first jig is insertedinto the electric pole shown in FIG. 18 according to the fourthembodiment;

FIG. 24 is a view showing a final state that the first jig is insertedinto the electric pole shown in FIG. 18 according to the fourthembodiment;

FIG. 25 is a view showing the first jig in the final state and thesecond jig is being inserted through a second opening portion into theinner hollow portion, respectively, according to the fourth embodiment;

FIG. 26 is a view showing a minasiki jig combination comprising thefirst and second jigs which is already inserted in the inner hollowportion of the electric pole shown in FIG. 18 according to the fourthembodiment;

FIG. 27 is a view showing the minasiki jig combination in view of adirection indicated by an arrow “A” in FIG. 26 according to the fourthembodiment;

FIG. 28 is a view showing the minasiki jig combination in view of adirection indicated by an arrow “B” in FIG. 26 according to the fourthembodiment; and

FIG. 29 is a view showing a modification of the minasiki jig combinationin view of a direction indicated by an arrow “B” in FIG. 26 according tothe fourth embodiment.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments of the present invention will be described hereinafter withaccompanying drawings.

First Embodiment

A first embodiment of the present invention will be describedhereinafter with reference to FIGS. 1 to 3.

A method of reinforcing an existing concrete electric pole, referred tosimply as “electric pole”, according to the first embodiment has a stepof injecting a reinforcing member in the electric pole through itsinjection hole portion such as an earth hole or the like previouslyformed to a predetermined position of a side wall of the electric poleabove the surface of the ground therearound.

This method according to the first embodiment is mainly adopted whenreinforcing a part of the electric pole adjacent to the boundary portionthereof under the earth hole.

FIG. 1 is a partially longitudinal cross sectional view showing astructure of an electric pole 1 which is already reinforced by thereinforcing method according to the first embodiment.

As shown in FIG. 1, the reinforced electric pole 1 is installed underthe ground so as to stand the surface S thereof and has a substantiallytubular shape to be gradually tapered toward its top portion.

In the first embodiment, the surface S of the ground is reinforced withblocks or the like so as to be inclined in order to prevent a landslideof the ground from occurring.

The reinforced electric pole 1 is provided with an annular side wall 101composed of reinforced concrete and an inner hollow portion 103 providedinside of the annular side wall 101.

The reinforced electric pole 1 is formed with an earth hole 105previously penetrated through a predetermined position of the annularside wall 101 of the electric pole 1 above the surface S of the groundtherearound.

The reinforced electric pole 1 is provided with a mortar-filled portion(mortar-filled layer) 106 which is located under the ground and isformed with a predetermined amount of mortar injected from the earthhole 105 to be filled in the inner hollow portion 103 of the lowerportion of the pole 1 under the ground.

A top portion of the mortar-filled portion 106 is positioned to asubstantially from 400 mm to 800 mm below the surface S of the groundand served as a base of a reinforcing portion described hereinafter.

The reinforced electric pole 1 is also provided with the reinforcingportion (reinforcing layer) 107 formed with reinforcing member injectedfrom the earth hole 105 to be filled in the inner hollow portion 103 onthe mortar-filled portion 106 of the pole 1 up to the vicinity of theearth hole 105.

The earth hole portion 105 from which the mortar and the reinforcingmember are injected has a substantially elliptical shape. The earth holeportion 105 has a major axis of substantially from 40 to 60 mm, and aminor axis of substantially from 20 to 40 mm.

The predetermined position of the annular side wall 101 to which theearth hole portion 105 is provided is usually located at a heightranging from substantially 1200 mm to substantially 1600 mm with respectto the surface S of the ground.

As the reinforcing member constituting the reinforcing portion 107, amixture is used, which is composed of hardened resin such as epoxy resinand aggregates such as gray irons. The mixture is formed by mixing thehardened resin with the aggregates so that the strength of the mixtureis more increased.

In FIGS. 1 and 2, the reference numeral 107 a shows the resincorresponding to the area including black points in FIGS. 1 and 2, andthe reference numeral 107 b shows the gray irons corresponding to theshadow areas therein.

Incidentally, the reinforcing member according to the first embodimentis not limited to the mixture. That is, for example, concrete may beused for the resin 107 a, and/or single chains composed of aramid may beused for the gray irons.

As the reinforcing member, unshrinkable mortar which is not shrinkableeven if it is solidified is may be used.

On the other hand, it may be possible to fill a predetermined amount ofpieces of sand and/or a predetermined amount of pieces of gravel in theinner hollow portion 103 of the electric pole 1 to form themortar-filled portion in place of filling the mortar therein.

FIG. 3A is a flowchart showing a working procedure of reinforcing theelectric pole 1 a which has not been reinforced yet according to thefirst embodiment. FIG. 3B pictorially shows the working procedure shownin FIG. 3A.

The reinforcing work according to the first embodiment will be describedhereinafter with reference to FIGS. 3A and 3B.

At first, a predetermined amount of poor mortar M which is served as abase of the reinforcing portion 107 is injected from the earth hole 105to be filled in the inner hollow portion 103 of the lower portion of thepole 1 a under the ground, forming the mortar-filled portion 105 therein(step S1).

The amount of injecting mortar varies in accordance with the conditionsof the electric pole 1 a including the capacity thereof and so on sothat, in the first embodiment, the amount of injecting mortar isadjusted so that the top portion of the mortar-filled portion 106 ispositioned to a substantially from 400 mm to 800 mm below the surface Sof the ground.

Next, the reinforcing member R composed of the mixture of the resin 107a and the gray irons 107 b is injected from the earth hole 105 to befilled in the inner hollow portion 103 on the mortar-filled portion 106of the electric pole 1 a up to the vicinity of the earth hole 105 (stepS13).

In this first embodiment, in step S13, because the earth hole portion105 is located to the predetermined position of the annular side wall101 at the height ranging from substantially 1200 mm to substantially1600 mm with respect to the surface S of the ground, the injecting worksare carried out through the earth hole portion 105.

However, in step S13, the injection works may be carried out throughanother hole portion formed to a predetermined position of the annularside wall 101 to be penetrated therethrough, predetermined positionwhich is adjacent to at least one of the scaffold volts mounted on theannular side wall 101.

The described procedure of the reinforcing work is carried out inaccordance with the described procedure shown in FIG. 3 so that thereinforced electric pole 1 shown in FIGS. 1 and 2 is accomplished.

After carrying out the work shown in step S13, in cases where it can beaccepted to reinforce the reinforced electric pole 1 from the outerperiphery thereof after sufficient consideration of constrains due tothe installation requirements of the electric pole 1 and the reinforcingcost thereof, it may be possible to wind a seat member such as an aramidfiber seat or the like around an outer periphery of a portion of theannular side wall 101, portion which ranges from the boundary portion ofthe electric pole 1 to the hole portion 103.

As described in step S13, in cases where no earth hole 105 is providedor a portion of the electric pole 1 which is higher than the earth hole105 is to be reinforced, at least one of the scaffold volts mounted on apredetermined position of the annular side wall 101 is removed therefromso that a hole portion is formed on the removed position with a drill orother similar devices so as to be communicated to the inner hollowportion 103. The formed hole portion allows the mortar and thereinforcing member to be injected into the inner hollow portion 103,making it possible to carry out the above reinforcing method accordingto the first embodiment.

As described above, according to the first embodiment of the presentinvention, it is possible to simply reinforce a portion of the electricpole 1 the earth hole 105 of which is located higher than the potion ofthe electric pole 1 to be reinforced.

In addition, the mortar and the gray irons are not only cheaper than anaramid fiber seat used for the conventional reinforcing method but alsohave no need of excavating the surface S of the ground around theboundary portion of the electric pole, and of carrying out demolitionand restoration works therearound, making it possible to reduce the costof the reinforcing work of the electric pole.

In the first embodiment, even in cases where the electric pole isinstalled on a special location at which it seems extremely hard toreinforce the electric pole, such as a location close to at least one ofstructures such as a house, or a location with a surface of the groundwhich is reinforced with blocks or the like so as to be inclined inorder to prevent a landslide of the ground from occurring as shown inFIG. 1, using the reinforcing method according to the first embodimentallows the reinforcing work to be easily carried out, obtainingespecially considerable effects when the electric pole installed on sucha special location.

Incidentally, applicants performed experiments in checking the strengthof the reinforced electric pole reinforced by the reinforcing methodaccording to the first embodiment so that it was demonstrated that thereinforced electric pole reinforced by the reinforcing method accordingto the first embodiment had substantially the same strength of aconventional reinforced pole reinforced by the conventional reinforcingmethod or more strength than the strength of the conventional reinforcedpole. Concretely, when reinforcing the electric pole with one part ofits annular side wall being cut, one part which corresponds to asubstantially 30 to 50% of the whole annular side wall, a checkedstrength that satisfies the designed strength usually required for anelectric pole was obtained.

Second Embodiment

A second embodiment of the present invention will be describedhereinafter with reference to FIGS. 4 to 6.

A method of reinforcing an electric pole according to the secondembodiment has a step of removing a cover composed of concrete andfitted in a top opening portion of an annular side wall, and injecting areinforcing member in the electric pole through the top opening portionof the annular side wall so as to reinforce the electric pole.

This reinforcing method can be applied to reinforcing a middle portionof the electric pole in accordance with the aging change thereof due totransformers mounted on the upper portion of the electric pole and/orcables installed between the electric pole and another electric poles.

FIG. 4 is a partially longitudinal cross sectional view showing astructure of an electric pole 2 which is already reinforced by thereinforcing method according to the second embodiment.

As shown in FIG. 4, the reinforced electric pole 2 is installed underthe ground so as to stand the surface S thereof and has a substantiallytubular shape to be gradually tapered toward its top portion, similar tothe first embodiment.

The reinforced electric pole 2 is provided with an annular side wall 201composed of reinforced concrete and an inner hollow portion 203 providedinside of the annular side wall 201.

The annular side wall 201 is formed at its top portion with a topopening portion TP communicated to the inner hollow portion 203.

The reinforced electric pole 2 is provided with a mortar-filled portion206 which is located under the ground and is formed with a predeterminedamount of mortar injected from the top opening portion TP to be filledin the inner hollow portion 203 of the lower portion of the pole 2 underthe ground.

A top portion of the mortar-filled portion 206 is positioned to, forexample, a substantially from 400 mm to 800 mm below the surface S ofthe ground and served as a base of a reinforcing portion describedhereinafter.

The reinforced electric pole 2 is also provided with the reinforcingportion 207 provided in the inner hollow portion 203 of the electricpole 2 on the mortar-filled portion 206 thereof.

As shown in FIGS. 4 and 5, the reinforcing portion 207 is formed with areinforcing member 207 ab mounted on the mortar-filled portion 206 andfilling material 207 c filled in a gap between the reinforcing member207 ab and the inner hollow portion 203 so that the reinforcing member207 ab is arranged substantially in the longitudinal direction (axialdirection) of the electric pole 2.

The reinforcing member 207 ab comprises a plurality of aramid rods 207 amounted on the top portion of the mortar-filled portion 206 and a fixingmember 207 b mounted on the mortar-filled portion 206 by which theplurality of aramid rods are fixed to be assembled.

Each of the aramid rods 207 a has a substantially 15 to 25 mm indiameter, and preferably, has a substantially 15 to 20 mm in diameter.

Furthermore, the electric pole 2 is provided with a cover 213 composedof concrete and fitted in the top opening portion TP of the annular sidewall 201.

In FIG. 5, only two aramid rods 207 a are shown in order to avoid FIG. 5becomes more complicated, but, approximately six to ten aramid rods 207a are usually fixed to the fixing member 207 b. The number of aramidrods 207 a fixed to the fixing member 207 b are determined depending ona diameter (bore diameter) of the inner hollow portion 203, the degreerequired for reinforcement and the like.

The longitudinal length of the reinforcing member 207 ab is accordinglyadjusted depending on the requirements of a portion of the electric pole2 to be reinforced. For example, when reinforcing both of the boundaryportion with respect to the surface S and the middle portion of theelectric pole 2, the longitudinal length of the reinforcing member 207ab is adjusted so that, in a state that the reinforcing member 207 ab isinserted in the inner hollow portion 203 and mounted on themortar-filled portion 206, the top portion of the reinforcing member 207ab is reached up to the height adjacent to the position at which cablesare installed, height which is substantially 3800 mm to 5500 mm from theboundary portion of the electric pole 2. After the length of thereinforcing member is adjusted, the adjusted reinforcing member may beinserted from the top opening portion TP of the annular side wall 201into the inner hollow portion 203.

Incidentally, the reinforcing member is not limited to the structureshown in FIG. 5.

That is, as shown in FIG. 6, the reinforcing member 207 ab 1 comprisesan aluminum plate 207 e mounted on the top portion of the mortar-filledportion 206 and a plurality of aramid chains 207 d composed of aramidfiber and joined to the aluminum plate 207 e. In this case, thelongitudinal length of the aluminum plate 207 e and that of each of thearamid chains 207 d are adjusted so that the aluminum plate 207 e islocated to the inside of the middle portion to which reinforcement ismostly required. In FIG. 6, a vinyl plate with both surfaces on whicharamid fiber seats are affixed may be used in place of the aluminumplate 207 e.

Unshrinkable mortar which, while the unshrinkable mortar is filled inthe gap between the reinforcing member 207 ab and the inner hollowportion 203, allows its strength to be increased and is not shrinkableeven if it is solidified may be used as the filling material 207 c.Moreover, resin such as epoxy, concrete or other similar material may beused as the filling material 207 c.

The amount of injecting mortar is adjusted in a similar manner to thefirst embodiment. Moreover, similarly to the first embodiment, apredetermined amount of pieces of sand and/or a predetermined amount ofpieces of gravel may be injected in the inner hollow portion 203 of theelectric pole 2 in place of the predetermined amount of mortar.

FIG. 7A is a flowchart showing a working procedure of reinforcing theelectric pole 2 a which has not been reinforced yet according to thesecond embodiment. FIG. 7B pictorially shows the working procedure shownin FIG. 7A.

At first, the cover 213 is removed from the top opening portion TP ofthe electric pole 2 a, and a predetermined amount of poor mortar M1which is served as a base of the reinforcing portion 207 is injectedfrom the top opening portion TP to be filled in the inner hollow portion203 of the lower portion of the pole 2 a under the ground, forming themortar-filled portion 205 therein (step S21).

Next, the reinforcing member 207 ab which is previously assembled insuch a manner that the plurality of aramid rods 207 a are fixed to thefixing member 207 b is lifted up with a crane C or the like so that thereinforcing member 207 ab is inserted from the top opening portion TPinto the inner hollow portion 203 (step S23).

After carrying out the work in step S23, while the reinforcing member207 ab is lifted up by the crane C, the filling material 207 c isinjected from the top opening portion TP into the inner hollow portion203 up to the height adjacent to the top portion of the reinforcingmember 207 ab, causing the middle portion of the electric pole 2 a inwhich the reinforcing member 207 ab is inserted to be reinforced (stepS25).

Finally, the crane C is removed from the reinforcing member 207 ab sothat the cover 213 is fitted to the top opening portion TP of theelectric pole 2 a so that the reinforcing work is finished (step S27).

The reinforcing work is carried out in accordance with the describedprocedure shown in FIG. 7 so that the reinforced electric pole 2 shownin FIGS. 4 and 5 is accomplished.

Incidentally, after carrying out the work in step S27, in cases where itcan be accepted to reinforce the reinforced electric pole 2 from theouter periphery thereof after sufficient consideration of constrains dueto the installation requirements of the electric pole 2 and thereinforcing cost thereof, it may be possible to wind a seat member suchas an aramid fiber seat or the like around an outer periphery of theannular side wall 201. In particular, a seat member such as an aramidfiber may be wound around only an outer periphery of a portion of theannular side wall 201, portion which ranges from the boundary portion ofthe electric pole 2 to the vicinity of the top portion of thereinforcing portion 207.

The second embodiment of the present invention properly can obtain thesame effects of the first embodiment.

When reinforcing a middle portion of the electric pole or an upperportion of the electric pole with respect to the earth hole in additionto the boundary portion thereof, using the reinforcing method accordingto the second embodiment allows the reinforcing work to be easilycarried out, obtaining especially considerable effects.

Third Embodiment

A third embodiment of the present invention will be describedhereinafter with reference to FIGS. 8 to 17.

A method of reinforcing an electric pole according to the thirdembodiment has a step of forming at least two opening portions (a firstopening portion and a second opening portion) in an annular side wall ofthe electric pole, a step of injecting material for base such as piecesof mortar, pieces of sand or pieces of gravel from the first openingportion for forming a base for reinforcement into an inside of theannular side wall and a step of inserting a plurality of rod memberseach composed of aramid, which is referred to as “aramid rod”, from thesecond opening portion into the inside of the annular side wall.

In this third embodiment, the plurality of aramid rods as reinforcingmembers are inserted in the inside of the annular side wall of theelectric pole. A string member is connected to each of the aramid rods.Each string member connected to each aramid rod is connected througheach through hole of a jig for arranging each aramid rod in the insideof the annular side wall of the electric pole.

Handling the jig allows the plurality of aramid rods to be arranged inthe inner hollow portion at regular intervals thereamong.

Each of the aramid rods has a substantially 15 to 25 mm in diameter, andpreferably, has a substantially 15 to 20 mm in diameter.

As the string member connected to the aramid rod, a linear string, astainless wire or the like is used, and the string member has asubstantially 1 to 3 mm in diameter, and preferably, has a substantially1.5 mm in diameter.

The string member can be wound around an outer periphery of an upperportion of the aramid rod to be connected thereto, describedhereinafter, or the string member can be fixed with a screw or the liketo the outer periphery of the upper portion of the aramid rod to beconnected thereto.

FIG. 8 is a partially longitudinal cross sectional view showing astructure of an electric pole 3 which is already reinforced by thereinforcing method according to the third embodiment.

As shown in FIG. 8, the reinforced electric pole 3 is installed underthe ground so as to stand the surface S thereof and has a substantiallytubular shape to be gradually tapered toward its top portion, similar tothe first and second embodiments.

The reinforced electric pole 3 is provided with an annular side wall 301composed of reinforced concrete and an inner hollow portion 303 providedinside of the annular side wall 301.

The reinforced electric pole 3 is formed with a first opening portion305 a and a second opening portion 305 b penetrated throughpredetermined first and second positions of the annular side wall 301 ofthe electric pole 3 above the surface S of the ground.

In FIG. 8, the first position and the second position are axiallyarranged, but the present invention is not limited to the structure sothat the first and second opening portions may be located to desiredportions of the annular side wall above the surface S of the ground.

The reinforced electric pole 3 is provided with a base portion 306 whichis located under the ground and is formed with base members, such as apredetermined amount of mortar, a predetermined amount of pieces of sandor predetermined amount of pieces of gravel injected from the firstopening portion 305 a to be filled in the inner hollow portion 303 ofthe lower portion of the pole 3 under the ground.

A top portion of the base portion 306 is positioned to, for example, asubstantially from 400 mm to 800 mm below the surface S of the groundand served as a base of a reinforcing portion described hereinafter.

An earth hole, or a hole portion formed to a predetermined position ofthe annular side wall 301 to which at least one of the scaffold volts isremoved may be used as at least one of the first and second openingportions 305 a and 305 b, and in cases where no hole portions are formedto suitable portions of the annular side wall 301, the first and secondopening portions may be formed with a core sampling drill or the like.

The first position to which the first opening portion 305 a is formed islocated at a height ranging from substantially 1000 mm to substantially1200 mm with respect to the surface S of the ground, and the secondposition to which the second opening portion 305 b is formed is locatedat an upper side of the first position in the range of 200 mm to 300 mm.Incidentally, each of the first and second opening portions 305 a and305 b has a substantially elliptical shape. Each of the first and secondopening portions 305 a and 305 b has a major axis of substantially from40 to 60 mm, and a minor axis of substantially from 20 to 40 mm.

The reinforced electric pole 3 is also provided with the reinforcingportion 307 provided in the inner hollow portion 303 of the electricpole 3 on the base portion 306 thereof.

FIG. 9 is an enlarged perspective cross sectional view showing adetailed structure of the reinforcing portion 307.

As shown in FIGS. 8 and 9, the reinforcing portion 307 comprises aplurality of aramid rods 307 a mounted on the base portion 306, andfilling material 307 b filled in a gap between the aramid rods 307 a andthe inner hollow portion 303 so that the aramid rods 307 a are arrangedsubstantially in the longitudinal direction (axial direction) of theelectric pole 3.

String members 307 d are fixedly connected to one end portions (upperend portions) of the aramid rods 307 a, respectively.

That is, one end portion of the string member 307 d is wound around anouter periphery of the one end portion of the aramid rod 307 a to befixedly connected thereto, or the one end portion of the string member307 d is fixed with a screw or the like to the outer periphery of theone end portion of the aramid rod 307 d.

In FIG. 9, only six aramid rods 307 a are shown, but, the presentinvention is not limited to the structure.

That is, the number of aramid rods 307 a inserted in the inner hollowportion 303 are determined depending on a diameter of the inner hollowportion 303, the degree required for reinforcement and the like.

Each of the aramid rods 307 a has a longitudinal (axial) length ofsubstantially 1800 mm to 2000 mm, and the longitudinal length of eacharamid rod 307 a is accordingly adjusted depending on the requirementsof a portion of the electric pole 3 to be reinforced, similarly to thesecond embodiment.

Unshrinkable mortar which, while the unshrinkable mortar is filled inthe gap between the aramid rods 307 a and the inner hollow portion 303,allows its strength to be increased and is not shrinkable even if it issolidified may be used as the filling material 307 c. Moreover, resinsuch as epoxy, concrete or other similar material may be used as thefilling material 307 c.

The amount of injecting pieces of mortar, pieces of sand or pieces ofgravel is adjusted in a similar manner to the first and secondembodiments.

FIG. 10 is a view showing a reinforcing member arrangement jig used forthe reinforcing method according to the third embodiment.

As shown in FIG. 10, a jig 50 is provided with a base bar 50 a, and afirst, second and third rod-like supporting members 51, 52 and 53 eachcomposed of, for example, aluminum and having the same length in itslongitudinal direction.

The length of each of the supporting members 51, 52 and 53 issubstantially equal to a diameter (bore diameter) of the inner hollowportion 303 of the electric pole 3.

The first supporting member 51 is fixed on one end portion of the basebar 50 a, and the second and third supporting members 52 and 53 arerotatably supported at their middle portions to the first supportingmember 51 by a pin member 50 b.

The jig 50 is also provided with a pair of first and second handlingarms 55 and 56 which are attached to first and second portions of thesecond and third supporting members 52 and 53, respectively The distancebetween the first position and the pin member 50 b and that between thesecond position and the pin member 50 b are substantially equal to eachother.

Both end portions of each of the first, second and third supportingmembers 51, 52 and 53 are formed with through holes 54 allowing thestring members 307 d to be put therethrough.

Lengths of the formed positions of the through holes 54 from the pinmember 50 b are substantially the same.

In the third embodiment, because of assuming to insert six aramid rods307 a into the inner hollow portion 303 of the electric pole 3, sixthrough holes 54 are formed in the total of the jig 50.

The jig 50 is also provided at the first supporting member 51 with apair of stoppers 57 and 58 for releasably locking the second and thirdsupporting members 52 and 53.

When the second and third supporting members 52 and 53 are rotated(opened) away from the base bar 50 a by the first and second handlingarms 55 and 56 being handled to be moved toward other end portion of thebase bar 50 a, the stoppers 57 and 58 allow the second and thirdsupporting members 52 and 53 to be locked so that the first, second andthird supporting members 51, 52 and 53 are positioned at an angle of 60°(degrees) among them, making it possible to arrange the first, secondand third supporting members 51, 52 and 53 at the same intervals amongthem in a circumferential direction (rotational direction) with respectto the pin member 50 b.

That is, when the second and third supporting members 52 and 53 arelocked by the stoppers 57 and 58, each of the through holes 54 isarranged on a circle at the center of the pin member 50 b at the sameintervals among them in the circumferential direction.

FIG. 11 shows a state of the jig 50 in which the handling arms 55 and 56are handled to be moved toward the one end portion of the base bar 50 aso that the second and third supporting members 52 and 53 are rotatedtoward the base bar 50 a to be closed. The closed state of the jig 50shown in FIG. 11 allows itself to be inserted through the second openingportion 305 b.

FIG. 12A is a flowchart showing a working procedure of reinforcing theelectric pole 3 a which has not been reinforced yet according to thethird embodiment. FIG. 12B pictorially shows the working procedure shownin FIG. 12A.

At first, suitable portions of the annular side wall 301 are drilledwith the core sampling drill CS so that the first and second openingportions 305 a and 305 b are formed to the suitable portions of theannular side wall 301 (step S31).

Next, base members BM such as pieces of mortar, pieces of sand or piecesof gravel are injected from the first opening portion 305 a to be filledin the inner hollow portion 303 of the lower portion of the pole 3 aunder the ground, forming the base portion 306 therein (step S33).

After the work in step S33, the six aramid rods 307 a connected to thestring members 307 d are inserted through the second opening portion 305b into the inner hollow portion 303 to be mounted on the base portion306 (step S35). In step S35, each other end portion of each of thestring members 307 d is pulled away through the second opening 305 bfrom the inner hollow portion 303 to be exposed to the outside thereof.

FIG. 13 is a lateral cross sectional view at an upper side of the secondopening portion 305 b from the view of the upper side thereof, showing astate that the aramid rods 307 a are inserted in the inner hollowportion 303 of the electric pole 3 a.

Next, in step S37, the string members 307 d are put from their other endportions through the through holes 54 of the jig 50, respectively, andthe jig 50 is inserted from its one end portion through the secondopening portion 305 b into the inner hollow portion 303 of the electricpole 3 a, shown in FIG. 14.

Further, in step S37, the handling arms 55 and 56 are handled to bepulled in a direction away from the electric pole 3 a so that the secondand third supporting members 52 and 53 are rotated (opened) away fromthe base bar 50 a, whereby the first, second and third supportingmembers 51, 52 and 53 are locked to be positioned at an angle of 60°among them by the stoppers 57 and 58, respectively.

That is, the first, second and third supporting members 51, 52 and 53are positioned on a circular locus determined by the rotations of thesecond and third supporting members 52 and 53 at the same intervalsamong them in the circumferential direction with respect to the pinmember 50 b.

After the handling work, in step S37, the string members 307 d exposedout of the electric pole 3 are pulled in the direction away from theelectric pole 3 a so that the string members 307 d get to be tensioned,causing the aramid rods 307 a to be suspended by the jig 50, as shown inFIG. 15. In the state of the jig 50 shown in FIG. 15, the handling arms55 and 56, and the base bar 50 a are integratedly fixed by wrapping themwith a wrapping member such as a packing tape.

Because, in step S37, the first, second and third supporting members 51,52 and 53, that is all through holes 54 are positioned on the circularlocus at the same intervals thereamong, the aramid rods 307 a connectedto the tensioned string members 307 d and supported by the first, secondand third supporting members 51, 52 and 53 are positioned on thecircular locus at the same intervals in the circumferential direction,respectively, in the inner hollow portion 303.

FIG. 16 is a perspective view showing a state that all of the aramidrods 307 a are positioned on the circular locus at the same intervals inthe circumferential direction in substantially parallel to the axialdirection, respectively in the inner hollow portion 303.

Incidentally, the jig 50 shown in FIGS. 10, 11, 14, 15 and 16 is anexample of the jig. That is, the structure of jig is naturally changeddepending on the number of aramid rods 307 a inserted in the innerhollow portion 303 of the electric pole 3.

In cases of using any jig, when the supporting members are rotated to beopened, any jig has an invariant configuration such that all of thethrough holes are positioned on the circle determined with respect tothe pin member 50 b.

After this work in steps S35 and S37 such that all aramid rods 307 a arepositioned at the same intervals thereamong in the circumferentialdirection, the filling material 307 c is injected from the first openingportion 305 a into the inner hollow portion 303 up to the heightadjacent to the top portions of the aramid rods 307 a, while the allaramid rods 307 a are supported by the jig 50 (step S39).

After the injected filling material 307 c is solidified, the wrappingmember is demounted from the jig 50 to be released from its fixed state.Next, the handling arms 55 and 56 are moved toward the one end portionof the base bar 50 a so that the second and third supporting members 52and 53 are rotated toward the base bar 50 a to be closed, as shown inFIGS. 11 and 14. The jig 50 whose supporting members 52 and 53 becomethe closed state is pulled out from the inner hollow portion 303 throughthe second opening portion 305 b, removing the string members 307 fromthe through holes 54 of the jig 50, respectively (step S41).Incidentally, in step S41, it is possible to pull out the jig 50immediately after the filling material 307 c is filled. Moreover, partsof the string members 307 d which are exposed out of the electric pole 3a are cut.

After the work in step S41, the first and second opening portions 305 aand 305 b are sealed. When the earth holes are used as the first andsecond opening portions, earth hole covers are fitted in the earthholes. When the first and second opening portions are formed with thecore sampling drill, an aramid fiber seat may be wound around a portionof the outer periphery of the annular side wall including the formedfirst and second opening portions.

The reinforcing work is carried out in accordance with the describedprocedure shown in FIG. 12A so that the reinforced electric pole 3 shownin FIGS. 8 and 9 is accomplished.

Incidentally, after carrying out the work in step S41, in cases where itcan be accepted to reinforce the reinforced electric pole 3 from theouter periphery thereof after sufficient consideration of constrains dueto the installation requirements of the electric pole 3 and thereinforcing cost thereof, it may be possible to wind a seat member suchas an aramid fiber seat or the like around an outer periphery of theannular side wall 301.

The third embodiment of the present invention properly can obtain thesame effects of the first and second embodiments.

In addition, according to the third embodiment, the jig used forarranging the aramid rods in the inner hollow portion 303 of theelectric pole 3, allows the aramid rods to be easily fixed. Furthermore,it is possible to pull out the jig after the injected filling memberbeing solidified to repeatedly use the jig, thereby remarkablyshortening the working time of reinforcing the electric pole and savingthe cost of the working time.

Incidentally, the jig 50 is configured so that the handling arms 55 and56 allow the second and third supporting members 52 and 53 to berotated, but the present invention is not limited to the configuration.

For example, FIG. 17 shows a modification of the jig 60 according to thethird embodiment.

That is, similarly to the third embodiment, the jig 60 comprises a basebar 60 a corresponding to the base bar 50 a, a first, a second and athird supporting members 61, 62 and 63 corresponding to the first,second and third supporting members 51, 52 and 53. The both end portionsof each of the first, second and third supporting members 61, 62 and 63are formed with through holes 64 corresponding to the through holes 54.

In particular, in the modification, the jig 60 is provided with a firstand a second elastic members 65 and 66. The first elastic member 65 isconnected between the first supporting member 61 and the secondsupporting member 62, and the second elastic member 66 is connectedbetween the first supporting member 61 and the third supporting member66.

That is, while the second and third supporting members 62 and 63 areopened so that the first, second and third supporting members 61, 62 and63 are positioned at the same intervals among them in thecircumferential direction with respect to a pin member 60 bcorresponding to the pin member 50 b, the second supporting member 62 isbiased by the first elastic member 65 away from the first supportingmember 61 but the second supporting member 62 is locked by the stopper67. Similarly, the third supporting member 63 is biased by the secondelastic member 66 away from the first support member 61 but the thirdsupporting member 63 is locked by the stopper 68.

In cases of using the jig 60 shown in FIG. 17, at first, the jig 60 isinserted into the inner hollow portion 303 while the second and thirdsupporting member 62 and 63 are subjected to external forces to be movedagainst the biasing forces toward the first supporting member 61,respectively.

After inserting the jig 60 in the inner hollow portion 303, no externalforces are applied to the second and third supporting member 62 and 63so that they are automatically moved toward the first supporting member61 by the elastic forces of the elastic members 65 and 66, causing thesecond and third supporting member 62 and 63 to be locked by thestoppers 67 and 68, respectively.

As a result, the first, second and third supporting members 61, 62 and63 are automatically positioned at an angle of 60° among them in thecircumferential direction with respect to the pin member 60 b in theinner hollow portion 303.

Therefore, the jig 60 can not be pulled out from the inner hollowportion of the electric pole toward the outside thereof, so that a newjig 60 is used with executing each reinforcement. However, except forthis point, using the jig 60 allows similar effects of the thirdembodiment to be obtained.

Fourth Embodiment

A fourth embodiment of the present invention will be describedhereinafter with reference to FIGS. 18 to 29.

A method of reinforcing an electric pole according to the fourthembodiment, similarly to the third embodiment, has a step of forming atleast two opening portions (a first opening portion and a second openingportion) in an annular side wall of the electric pole, a step ofinjecting material for base such as pieces of mortar, pieces of sand orpieces of gravel from the first opening portion for forming a base forreinforcement into an inside of the annular side wall and a step ofinserting a plurality of reinforcing members from the second openingportion into the inside of the annular side wall.

As the reinforcing member, a plurality of aramid rods are used, but, inthe fourth embodiment, each of the reinforcing members is provided withan aramid rod and a special reinforcement. The special reinforcement hasan outer peripheral surface which is not flat and is fixedly connectedto one end portion (lower end portion) of the aramid rod with a fixingmember. The connection of the special reinforcement to the aramid rodcauses the reinforcing member to be increased in weight, preventing,after the injection of the filling material in the inner hollow portion,the reinforcing member from being floated due to buoyant force of thefilling material. The prevention of floating the reinforcing memberallows a reinforced portion in the inner hollow portion to be stable,making it possible to increase the reinforcing strength.

A string member is connected at its one end portion to each other endportion (upper end portion) of each of the aramid rods. Each stringmember connected to each aramid rod is also connected to a jig forarranging each reinforcing member in the inside of the annular side wallof the electric pole.

Handling the jig allows the plurality of reinforcing members to bearranged in the inside of the inner hollow portion at regular intervalsthereamong.

As the string member connected to the aramid rod, a linear string, astainless wire or the like is used, and the string member has asubstantially 1 to 3 mm in diameter, and preferably, has a substantially1.5 mm in diameter.

Each of the reinforcing members (each of the aramid rods and each of thespecial reinforcements) has a substantially 15 to 25 mm in diameter, andpreferably, has a substantially 15 to 20 mm in diameter.

The string member can be fixed to the reinforcing member in the samemanners according to the third embodiment.

The increase of the weight of the reinforcing member needs a more hardjig for arranging each reinforcing member in the inside of the annularside wall of the electric pole. Then, in the fourth embodiment, two jigsfor arranging each reinforcing member in the inside of the annular sidewall of the electric pole are used.

FIG. 18 is a partially longitudinal cross sectional view showing astructure of an electric pole 4 which is already reinforced by thereinforcing method according to the fourth embodiment.

As shown in FIG. 18, the reinforced electric pole 4 is installed underthe ground so as to stand the surface S thereof and has a substantiallytubular shape to be gradually tapered toward its top portion, similar tothe first, second and third embodiments.

The reinforced electric pole 4 is provided with an annular side wall 401composed of reinforced concrete and an inner hollow portion 403 providedinside of the annular side wall 401.

The reinforced electric pole 4 is formed with a first opening portion405 a and a second opening portion 405 b penetrated throughpredetermined first and second positions of the annular side wall 401 ofthe electric pole 4 above the surface S of the ground.

In FIG. 18, the first position and the second position are axiallyarranged, but the present invention is not limited to the structure sothat the first and second opening portions may be located to desiredportions of the annular side wall above the surface S of the ground.

An earth hole, or a hole portion formed to a predetermined position ofthe annular side wall 401 to which at least one of the scaffold volts isremoved may be used as at least one of the first and second openingportions 405 a and 405 b, and in cases where no hole portions are formedto suitable portions of the annular side wall 401, the first and secondopening portions may be formed with a core sampling drill or the like.

The first position to which the first opening portion 405 a is formedand the second position to which the second opening portion 405 b isformed are located similarly to the third embodiment.

The reinforced electric pole 4 is provided with a base portion 406 whichis located under the ground and is formed with base members, such as apredetermined amount of mortar, a predetermined amount of pieces of sandor a predetermined amount of pieces of gravel injected from the firstopening portion 405 a to be filled in the inner hollow portion 403 ofthe lower portion of the pole 4 under the ground, similarly to the thirdembodiment.

The reinforced electric pole 4 is also provided with the reinforcingportion 407 provided in the inner hollow portion 403 of the electricpole 4.

The reinforcing portion 407 comprises a plurality of reinforcing members408 each having an aramid rod 408 a. Each of the aramid rods 408 a has asubstantially 15 to 25 mm in diameter, and preferably, has asubstantially 17 to 19 mm in diameter.

The reinforcing member 408 also comprises a plurality of specialreinforcements (reinforcing bars) 408 b each having the same diameter ofeach of the aramid rods 408 a and mounted in the base portion 406. Thereinforcing member 408 further comprises a plurality of fixing members408 c for coaxially connecting the upper end portions of the specialreinforcements 408 b to the aramid rods 408 a, respectively.

Each string member 408 d has one and other end portions, and each oneend portion of which is fixedly connected to each upper end portion ofeach aramid rod 408 a.

The fixedly connecting manner of the string member 408 d and the aramidrod 408 a is similar to the third embodiment.

The reinforcing portion 407 further comprises a filling material 410filled in a gap between the aramid rods 408 a and the inner hollowportion 403 so that the aramid rods 408 a are arranged substantially inthe longitudinal direction (axial direction) of the electric pole 4.

The longitudinal length of the special reinforcement 408 b is adjustedso that, when the special reinforcement 408 b is fixedly connectedthrough the fixing member 408 c to the lower end portion of the aramidrod 408 a, the total longitudinal length of the aramid rod 408 a and thespecial reinforcement 408 b substantially equals to the range from thefirst opening portion 405 a to the boundary portion of the electric pole4. Therefore, the special reinforcement 407 b has a substantially 700 mmto 900 mm in longitudinal length, preferably, a substantially 800 mm.

The special reinforcement 408 b allows the weight of the reinforcingmember 408 itself to be stable, and prevents the reinforcing member frombeing floated after the injection of the filling material 410.

Moreover, because the total longitudinal length of the aramid rod 408 aand special reinforcement 408 b is reached up to substantially 2500 mmto 2900 mm, it is hard to transport the combination members eachconsisting of the aramid rod 408 a, the special reinforcement 408 b andthe fixing member 408 c.

Then, in the fourth embodiment, the aramid rods 408 a, the specialreinforcements 408 b and the fixing members 408 c are separatelytransported, and when the aramid rods 408 a, the special reinforcements408 b and the fixing members 408 c are reached at a location where theelectric pole 4 is installed, the aramid rods 408 a and the specialreinforcements 408 b are fixedly connected via the fixing members 408 c,respectively, assembling the reinforcing members 408. Therefore, it ispossible to easily carry out the transport of the reinforcing members.

FIG. 19 is a structural view showing a first jig 70 for arrangingreinforcing members used for the reinforcing method according to thefourth embodiment, and FIG. 20 is a structural view showing a second jig80 for arranging reinforcing members used for the reinforcing methodaccording to the fourth embodiment.

The first jig 70 shown in FIG. 19 is composed of a special reinforcingbar whose outer periphery is uneven.

The first jig 70 comprises a first supporting member 71 having asubstantially arc shape for supporting the reinforcing members 408, anda base bar 72 having one end portion to which the first supportingmember 71 is fixed so that an inner arc surface 71 a of the firstsupporting member 71 faces toward the direction away from the base bar72 in the longitudinal direction.

The first jig 70 is also provided with a plurality of suspendingportions 73 fixedly mounted on the inner arc surface 71 a by, forexample, welding.

Each of the suspending portions 73 has a through hole 73 a an axialdirection of which is orthogonal to the longitudinal direction of thebase bar 72 and to the radial direction of the first supporting member71.

Each of the suspending portions 73 is configured to allow the stringmember 408 d to be put therethrough.

That is, because the positions of the through holes 73 a are fixed, incases where the first jig 70 is arranged with the radial direction ofthe first supporting member 71 being horizontally positioned and otherend portions of the string members 408 d are put through the throughholes 73 a, when the other end portions of the string members 408 d arepulled, all of the string members 408 d are tensioned so that thereinforcing members 408 are supported by the through holes 73 a of thesuspending portions 73 of the first supporting member 71 in the axialdirection of each through hole 73 a.

The suspending portions 73 can be mounted on the inner arc surface 71 aat the same intervals in the circumferential direction.

In FIG. 19, only four suspending portions 73 are shown, but, the presentinvention is not limited to the structure.

That is, the number of suspending portions 73 are determined dependingon the number of the reinforcing members 408 and a diameter of the innerhollow portion 403, the degree required for reinforcement and the like.Furthermore, in FIG. 19, each of the through holes 73 a has asubstantially circular shape, but this structure is one example of thejig. That is, each of the through holes 73 a may have another shape suchas a substantially elliptical shape, or a substantially rectangularshape.

In addition, the first jig 70 comprises an eyehole portion 74 having aplurality of eyeholes 74 a each axial direction of which is parallel tothe longitudinal direction of the base bar 72. When the string members408 d are exposed from the through holes 73 a of the suspending portions73, the eyeholes 74 a allow the exposed string members 408 d to beeasily pulled out. The first jig 70 also comprises a handed portion 75having a substantially circular shape and formed on a middle portion ofthe base bar 72 so as to project orthogonally to the longitudinaldirection of the base bar 72. The handled portion 75 is configured toallow the first jig 70 to be handled so that it is easy to insert thefirst jig 70 into the inner hollow portion 403.

Furthermore, the first jig 70 comprises jig supporting portions 76formed on the base bar 72 so that the second jig 80 can be mounted to besupported when supporting the reinforcing members.

The number of jig supporting portions 76 is not limited to the two.

That is, desired number of jig supporting portions 76 may be formed onthe base bar 72 depending on the weight of the second jig 80.

The second jig 80 shown in FIG. 20 is composed of a special reinforcingbar similarly to the first jig 70.

The second jig 80 comprises a second supporting member 81 having asubstantially arc shape for supporting the reinforcing members 408, anda base bar 82 having one end portion to which the second supportingmember 81 is fixed so that an inner arc surface 81 a of the secondsupporting member 81 faces toward the base bar 72 itself in thelongitudinal direction.

The second jig 80 is also provided with a plurality of suspendingportions 83 fixedly mounted on the inner arc surface 81 a by, forexample, welding.

Each of the suspending portions 83 has a through hole 83 a an axialdirection of which is orthogonal to the longitudinal direction of thebase bar 82 and to the radial direction of the second supporting member81.

Each of the suspending portions 83 is configured to allow the stringmember 408 d to be put therethrough.

That is, because the positions of the through holes 83 a are fixed, incases where the second jig 80 is arranged with the radial direction ofthe second supporting member 81 being horizontally positioned and otherend portions of the string members 408 d are put through the throughholes 83 a, when the other end portions of the string members 408 d arepulled, all of the string members 408 d are tensioned so that thereinforcing members 408 are supported by the through holes 83 a of thesuspending portions 83 of the second supporting member 81 in the axialdirection of each through hole 83 a.

The suspending portions 83 can be mounted on the inner arc surface 81 aat the same intervals in the circumferential direction.

In FIG. 20, only four suspending portions 83 are shown, but, the presentinvention is not limited to the structure, similarly to the first jig70. Furthermore, in FIG. 20, each of the through holes 83 a has asubstantially circular shape, but this structure is one example of thejig, similarly to the first jig 70.

In addition, the second jig 80 comprises an eyehole portion 84 having aplurality of eyeholes 84 a which have substantially similar functions ofthe eyehole portion 74 and the eyeholes 74 a. Furthermore, the secondjig 80 also comprises a handed portion 85 which is similarly served asthe handled portion 85, and jig supporting portions 86 formed on thebase bar 82 so that the first jig 70 can be mounted to be supported whensupporting the reinforcing members, similarly to the first jig 70.

Each of the total axial lengths of each of the first and second jigs 70and 80 has a substantially 1000 mm to 1200 mm so that each size of eachof the first and second supporting members 71 and 81 is determinedaccording to the diameter of the inner hollow portion 403 of theelectric pole to be reinforced. An example of each arc length of each ofthe first and second supporting members 71 and 81 is substantially 230mm.

The first and second supporting members 71 and 81 are substantiallysymmetrical with each other. That is, when the first and secondsupporting members 71 and 81 are parallely arranged at different heightsso that the whole shape of the combination of the first and the secondsupporting members 71 and 81 parallely arranged at different heights inview of an upper side of the combination appears to be substantiallycircular shape.

Because the first and the second jigs 70 and 80 have a total of eightsuspending portions 73 and 83 which allow a total of eight reinforcingmembers 408 to be inserted through the eight suspending portions 73 and83 in the inner hollow portion 403.

The number of the reinforcing members 408 depending on the diameter ofthe inner hollow portion 403, the degree required for reinforcement andthe like. Hereinafter, the combination of the first and second jigs 70and 80 is also referred to as “minasiki jig combination” and assigned toa reference numeral of 90.

FIG. 21A is a flowchart showing a working procedure of reinforcing theelectric pole 4 a which has not been reinforced yet according to thefourth embodiment. FIG. 21B pictorially shows the working procedureshown in FIG. 21A.

At first, suitable portions of the annular side wall 401 are drilledwith the core sampling drill CS so that the first and second openingportions 405 a and 405 b are formed to the suitable portions of theannular side wall 401 (step S51).

Next, the reinforcing members 408 comprising the aramid rods 408 a andthe special reinforcements 408 b connected thereto are prepared. Thestring members 408 d are connected to the one end portions of the aramidrods 408 a.

Then, the reinforcing members 408 are inserted from their lower endportions through the second opening portion 405 b into the inner hollowportion 403 (step S53). In step S53, each other end portion of each ofthe string members 408 d is pulled away through the second opening 405 bfrom the inner hollow portion 403 to be exposed to the outside thereof.

Next, in step S55, the string members 408 d are put from their other endportions through the through holes 73 a and 83 a of the first and secondjigs 70 and 80, respectively.

Then, in step S55, the first and second jigs 70 and 80 are sequentiallyinserted from their lower end portions through the second openingportion 405 b into the inner hollow portion 403 of the electric pole 4a.

FIGS. 22 to 24 are views each explaining a procedure for inserting thefirst jig 70 into the inner hollow portion 403 of the electric pole 4 a.Incidentally, in FIGS. 22 to 24, for focusing on the procedure forinserting the first jig 70, the reinforcing members 408 already insertedin the inner hollow portion 403 and the string members 408 d are notshown.

At first, as shown in FIG. 22, the first supporting member 71 of thefirst jig 70 is inserted through the second opening portion 405 b intothe inner hollow portion 403 so that each axial direction of eachthrough hole 73 a of the first supporting member 71 is orthogonal to theaxial direction (longitudinal direction) of the electric pole 4 a.

When the length of the second opening portion 405 b in the axialdirection of the electric pole 4 is smaller than the arc length of thefirst supporting member 71, the first supporting member 71 is insertedwith being rotated into the inner hollow portion 403.

FIG. 23 is a view showing a state that the base bar 72 of the first jig70 is arranged in orthogonal to the axial direction and each axialdirection of each through hole 73 a is orthogonal to the axial directionof the electric pole 4 a, too.

From the state of the first jig 70 shown in FIG. 23, the handled portion75 of the first jig 70 is handled so that the first jig 70 is rotatedaround its an axial direction of the base bar 72 at an angle of 90° sothat each axial direction of each through hole 73 a is parallel to thelongitudinal direction of the electric pole 4 a, as shown in FIG. 24.

The state of the first jig 70 shown in FIG. 24, that is, the state thatthe first supporting member 71 is arranged in the inner housing portion403 so that each axial direction of each through hole 73 a is parallelto the longitudinal direction of the electric pole 4 a allows thereinforcing members 408 to be arranged and fixed in the inner hollowportion 403, being referred to as “final state” hereinafter.

After the first jig 70 is made the final state, the second supportingmember 81 of the second jig 80 is inserted through the second openingportion 405 b into the inner hollow portion 403 while the first jig 70is supported with its final state being kept.

FIG. 25 is a view showing the first jig 70 in the final state and thesecond supporting member 81 of the second jig 80 is being insertedthrough the second opening portion 405 b into the inner hollow portion403, respectively. Incidentally, insertion of the second supportingmember 81 of the second jig 80 is carried out substantially similarly tothe insertion of the first supporting member 71 of the first jig 70.

That is, as shown in FIG. 25, the second supporting member 81 isinserted with being rotated into the inner hollow portion 403 and thesecond supporting member 81 is arranged so that each axial direction ofeach through hole 83 a is parallel to the longitudinal direction of theelectric pole 4 a. Incidentally, because the insertion of the secondsupporting member 81 into the inner hollow portion 403 is substantiallythe same as that of the first supporting member 71, omitting thedetailed explanation of the insertion of the second supporting member81.

Then, FIG. 26 is a view showing the minasiki jig combination 90comprising the first and second jigs 70 and 80 which are alreadyinserted in the inner hollow portion 403 of the electric pole 4 a.

That is, as shown in FIG. 26, the first and second supporting members 71and 81 are parallely arranged at different heights. Namely, the secondsupporting member 81 is higher than the first supporting member 71.

In addition, as shown in FIG. 26, the minasiki jig combination 90comprising the first and second jigs 70 and 80 is connected to a jigsupporting member 91 winding around the outer periphery of the electricpole 4 a by fixing members such as a band 92 and wires 94. Each wire 94is provided at its middle portion with an adjusting element 93 foradjusting the length of the each wire 94. Incidentally, the wires 94 areshown by dashed line and solid line in FIG. 26, respectively, the formerof which is positioned to a backside of the electric pole 4 a in FIG.26.

FIG. 27 is a view showing the minasiki jig combination 90 in view of thedirection indicated by the arrow “A” in FIG. 26, and FIG. 28 is a viewshowing the minasiki jig combination 90 in view of the directionindicated by the arrow “B” in FIG. 26, that is, in view of the upperside of the minasiki jig combination 90. In each of FIGS. 27 and 28,only minasiki jig combination 90 is shown in order to simplify each ofFIGS. 27 and 28.

As shown in FIG. 28, the whole shape of the combination of the first andthe second supporting members 71 and 81 parallely arranged at differentheights in view of an upper side of the combination appears to besubstantially circular shape.

That is, when eight reinforcing members 408 are inserted in the innerhollow portion 403, as shown in FIG. 28, at least eight suspendingportions 73 and 83 need to be mounted on the first and second supportingmembers 71 and 81 so that the suspending portions 73 and 83 (throughholes 73 a and 83 a) are arranged at the same angle of substantially 45°thereamong in the circumferential direction and each axial direction ofeach through hole 73 a and 83 a is substantially parallel to thelongitudinal direction.

Incidentally, when six reinforcing members 408 are inserted in the innerhollow portion 403, at least six suspending portions 73 and 83 need tobe mounted on the first and second supporting members 71 and 81 so thatthe suspending portions 73 and 83 (through holes 73 a and 83 a) arearranged at the same angle of substantially 60 thereamong in thecircumferential direction and each axial direction of each through hole73 a and 83 a is substantially parallel to the longitudinal direction,shown in FIG. 29.

Then, after fixedly supporting the minasiki jig combination 90 by thefixing members, in step S55, the exposed string members 408 d out of theinner hollow portion 403 of the electric pole 4 a through the secondopening portion 405 b are pulled away from the electric pole 4 a so thatthe string members 408 d get to be tensioned, causing the reinforcingmembers 408 to be suspended by the suspending portions 73 and 83(through holes 73 a and 83 a), as shown in FIG. 26.

Because, in step S55, the suspending portions 73 and 83 (through holes73 a and 83 a) are arranged at the same angle of substantially 60° thatis the same intervals thereamong in the circumferential direction andeach axial direction of each through hole 73 a and 83 a is substantiallyparallel to the longitudinal direction, the reinforcing members 408connected to the tensioned string members 408 d and supported by thesuspending portions 73 and 83 are positioned at the same intervals inthe circumferential direction, respectively, in the inner hollow portion403.

After this work in step S55 such that all reinforcing members 408 arefixedly positioned at the same intervals thereamong in thecircumferential direction, base members such as pieces of mortar, piecesof sand or pieces of gravel are injected from the first opening portion405 a to be filled in the inner hollow portion 403 of the lower portionof the pole 4 a up to the height adjacent to the fixing members 408 c ofthe reinforcing members 408, while the reinforcing members 408 aresupported by the first and second jigs 70 and 80. The injected basemembers cause the base portion 406 in the inner hollow portion 403 ofthe electric pole 4 a (step S57).

Next, the filling material 410 is injected from the first openingportion 405 a into the inner hollow portion 403 up to the heightadjacent to the top portions of the reinforcing members 408 (aramid rods408 a) while the reinforcing members 408 are supported by the first andsecond jigs 70 and 80 (step S59).

After the injected filling material 410 is solidified, the minasiki jigcombination 90, that is, the first and second jigs 70 and 80 are pulledout of the inner hollow portion 403 (step S61). This pulling out step iscarried out in the reverse procedure of inserting the first and thesecond supporting members 71 and 81 of the first and second jigs 70 and80 into the inner hollow portion 403 of the electric pole 4 a.

Incidentally, in step S61, the filling material 410 has some degree ofviscosity, allowing the first and the second jigs 70 and 80 to be pulledout immediately after the work in step S59. After the work in step S61,parts of the string members 408 d which are exposed out of the electricpole 4 a are cut, and remained parts of which are inserted into theinner hollow portion 403 of the electric pole 4 a.

In addition, when the filling material 410 is filled up to the vicinityof the first opening portion 405 a, the injection of the fillingmaterial 410 may be once stopped so that the minasiki jig combination 90is removed out of the inner hollow portion 403, and after that, thefilling material 410 may be injected from the second opening portion 405b once again, whereby the reinforcing members 408 can be completelyburied. In this case, because the filling material 410 is injected up tothe height which is higher than the first opening portion 405 a, thefirst opening portion 405 a may be sealed by any one of sealing methods.

The above working procedure from step S51 to S61 are an example so thatother procedures may be used in the range of the scope of the presentinvention.

Working procedure after step S61 is the same as the working procedureaccording to the third embodiment.

That is, the reinforcing work is carried out in accordance with thedescribed procedure shown in FIG. 21A so that the reinforced electricpole 4 shown in FIG. 18 is accomplished.

Incidentally, after carrying out the work in step S61, in cases where itcan be accepted to reinforce the reinforced electric pole 4 from theouter periphery thereof after sufficient consideration of constrains dueto the installation requirements of the electric pole 4 and thereinforcing cost thereof, it may be possible to wind a seat member suchas an aramid fiber seat or the like around an outer periphery of theannular side wall 401.

In addition, in cases where it is impossible to excavate the surface ofthe ground around the boundary portion of the concrete electric pole, aseat member such as an aramid fiber may be wound around only an outerperiphery of a portion of the annular side wall 401, portion whichranges from the boundary portion of the electric pole 4 to the vicinityof the first opening portion and/or the second opening portion. Thismodification allows the strength of the electric pole to be moreincreased.

Furthermore, applicants performed bend test (JISA 5373) of thereinforced electric pole reinforced by using the above reinforcingmethod according to the fourth embodiment so that, in cases where thereinforced electric pole has 500 kg in weight, safety factor ofsubstantially 2.3 to 2.6 was obtained, and in cases where the reinforcedelectric pole has 700 kg in weight, safety factor of substantially 2.1to 2.4 was obtained. These safety factors exceed the standard safetyfactor of 2 naturally required for the strength of electric poles,showing that the reinforcing method according to the fourth embodimentcan provide a sufficient strength to the reinforced electric poles.

The fourth embodiment of the present invention properly can obtain thesame effects of the first, second and third embodiments.

In addition, in the fourth embodiment, the special reinforcements 408 bconnected to the aramid rods 408 a allow the weights of the reinforcingmembers 408 themselves to be stable, preventing the reinforcing members408 from being floated after the injection of the filling material 410,and increasing the reinforcing strength of the electric pole 4.

Furthermore, in the fourth embodiment, it is possible to provide theminasiki jig combination 90 comprising the first jig 70 and the secondjig 80 which can stably support and fix the reinforcing members even ifeach of them has the special reinforcement and large weight.

The reinforcing method according to the fourth embodiment can be appliedto reinforcing a middle portion of the electric pole in accordance withthe aging change thereof due to transformers mounted on the upperportion of the electric pole and/or cables installed between theelectric pole and another electric poles.

Incidentally, in each of the embodiments, the annular side wall of theelectric pole may have a circular shape, an elliptic shape, arectangular shape or the like in its lateral cross section.

While there has been described what is at present considered to be thepreferred embodiments and modifications of the present invention, itwill be understood that various modifications which are not describedyet may be made therein, and it is intended to cover in the appendedclaims all such modifications as fall within the true spirit and scopeof the invention.

The entire contents of Japanese Patent Application 2002-38252 filed onFeb. 15, 2002, Japanese Patent Application 2002-132022, and JapanesePatent Application 2002-204901 are incorporated herein by reference.

1-15. (canceled)
 16. A reinforced concrete pole, comprising: an annularside wall having an inner hollow portion provided therein; and anopening portion formed in the annular side wall, wherein a base portionin the inner hollow portion of a lower portion of the concrete poleincludes at least one of a predetermined amount of mortar, apredetermined amount of sand and a predetermined amount of gravel, and areinforcing member is in the inner hollow portion on the base portion.17. A reinforced concrete pole, comprising: an annular side wall havingan inner hollow portion provided therein; and an opening portion formedin the annular side wall, wherein a base portion in the inner hollowportion of a lower portion of the concrete pole includes at least one ofa predetermined amount of mortar, a predetermined amount of sand and apredetermined amount of gravel; and wherein a reinforcing member is inthe inner hollow portion on the base portion, and filling material is ina gap between the reinforcing member and the inner hollow portion.
 18. Areinforced concrete pole having an annular side wall, an inner hollowportion provided therein and an opening portion formed in the annularside wall reinforced by a method comprising the steps of: injecting atleast one of a predetermined amount of mortar, a predetermined amount ofsand and a predetermined amount of gravel into the inner hollow portionof the electric pole through the opening portion; preparing a jigmember; inserting a reinforcing member for reinforcing the electric poleinto the inner hollow portion of the electric pole through the openingportion while the reinforcing member is supported by the jig member; andwhile the inserted reinforcing member is supported by the jig member,injecting filling material into a gap between the inserted and supportedreinforcing member and the inner hollow portion. 19-27. (canceled)